1. Field
This invention relates generally to packaged semiconductor devices, and more specifically to a semiconductor device encapsulant that is compatible with copper wire bonding.
2. Related Art
Electronic devices such as semiconductor devices can be encapsulated in an encapsulant such as a mold compound. The concentrations of ions in a mold compound are typically determined via aqueous extraction under elevated temperature and pressure, and then analysis by a method such as ion chromatography. The mold compound must be finely ground (e.g., 100% of particles no greater than 10 μm) before the extraction in order to extract all of the ions from the mold compound, which is required to correctly determine the ion concentrations. One gram of finely ground cured mold compound is then added to ten milliliters of ultra-pure water and then mixed for approximately two hours. The mix is then sealed in a high purity bomb and heated to 120-190° C. for a time (e.g., 24 hours at 120° C.). The extract is then filtered and tested to determine the concentration of ionic species and the pH (e.g., using ion chromatography). The measured ionic concentrations in the sample are then translated for the bulk mold compound based on the amount of water that was used. The ionic concentrations, which are determined by the aqueous extraction and analysis (or another methodology), are then attributed to be the ionic concentrations in the cured bulk mold compound, and the pH of the aqueous extract is attributed to be the pH of the bulk mold compound due to absorbed water.